676 FIORDS, OR DEEP COAST CHANNELS. 
are generally confined to certain latitudes, we see that it is altogether 
improbable that they are a result of fissures or subsidences of the crust. 
To suppose that these particular regions, mostly destitute of traces of 
volcanic action, should be thus rent, while other regions, the most re- 
markable for volcanoes and earthquakes in the world, have a nearly 
unbroken coast, would be an assumption wholly unwarranted. 
Denudation, then, by some means, was probably their origin. We 
have already shown that the sea is incapable of excavating valleys in 
coasts. ‘These fiords would seem at first to be direct evidence to the 
contrary. But those who have examined them know that the waters 
within have the quietness of an inland stream, and rise and fall with 
the tides without commotion, unless passages open through from one 
to another, so as to produce a complete circuit for the waters. ‘These 
channels, therefore, are not increasing in depth by the action of the 
sea. ‘The waves wear the capes, as elsewhere on coasts, and tend to 
fill up the narrow bay at its head. The exceptions in the case of 
those channels which have openings by two channels to their head, 
do not affect the general question, as this is not their usual character. 
Subaerial denudation is our last cause,—the only other mode of 
origin to which we can appeal. And this implies that the land was 
higher above the sea when subjected to this wear; and also that the 
fiords were originally the valleys of the land. The subsidence of a 
country, continued till its alluvial region along the coast is submerged, 
will necessarily make deep bays of its long linear valleys; and this is 
the view to which we are directed by the investigation of this subject. 
In our remarks on the Pacific Ocean, we presented the same argu- 
ment, applying it to the Gambier Islands. Mangareva, in its long pro- 
jecting points stretching out on every side, with deep bays between, 
so resembles what Tahiti would become, if submerged to the extent 
which has undoubtedly taken place at the Gambiers, that the evi- 
dence there cannot be mistaken. And it must be acknowledged that the 
same kind of evidence of a submergence is applicable to other coasts. 
The countries where these fiords occur are mountainous regions, 
whose interior is deeply cut up with valleys having the same general 
direction, that is, towards the sea. The cases, therefore, are exactly 
parallel with that of the Pacific island, and consequently we must 
admit an extensive submergence of all the coasts where these fiords 
occur. 
The fact of such a submergence is also evident from the great num- 
ber of rocky islands and islets off such coasts, as may be seen on any 
